Method for monitoring performance of marine seismic air gun arrays

Abstract

A method for characterizing function of an air gun includes measuring, with respect to time, a parameter related to pressure in a charge chamber portion of the air gun. The measurements with respect to time are used to characterize the function of the air gun.

1. A method for characterizing a function of an air gun, comprising:
 measuring, with respect to time, a parameter related to pressure in a charge storage chamber portion of the air gun; 
 using the parameter measured with respect to time to characterize the function of the air gun. 
 
   
   
     2. The method of  claim 1  wherein the parameter comprises pressure. 
   
   
     3. The method of  claim 1  wherein the parameter comprises a time derivative of pressure. 
   
   
     4. The method of  claim 1  wherein the characterizing comprises determining a firing instant of the air gun. 
   
   
     5. The method of  claim 1  wherein the characterizing comprises determining an existence of a leak in the air gun. 
   
   
     6. The method of  claim 1  wherein the characterizing comprises determining an inadequate charge storage chamber pressure prior to firing the air gun. 
   
   
     7. The method of  claim 1  wherein the characterizing comprises determining a failure of the air gun to fire upon receipt thereof of a firing trigger signal. 
   
   
     8. The method of  claim 1  wherein the characterizing comprises determining a firing of the air gun absent receipt thereof of a firing trigger signal. 
   
   
     9. The method of  claim 1  further comprising measuring temperature in the charge storage chamber, and delaying use of seismic signals generated by the air gun until the measured temperature reaches a selected value. 
   
   
     10. The method of  claim 1  further comprising measuring humidity in the charge storage chamber, and determining a presence of water from the humidity measurement. 
   
   
     11. The method of  claim 10  further comprising operating the air gun until the water is substantially removed from the charge storage chamber. 
   
   
     12. The method of  claim 1  further comprising repeatedly actuating the air gun, repeatedly measuring the parameter related to pressure during each actuation and determining a fault in operation of the air gun when a change in the measured parameter exceeds a selected threshold for at least one actuation of the air gun. 
   
   
     13. The method of  claim 1  further comprising measuring with respect to time a parameter related to pressure in a charge storage chamber of each of a plurality of air guns, and using the measured parameter to characterize the function of each air gun. 
   
   
     14. The method of  claim 13  further comprising controlling a pressure in each charge storage chamber in response to the measured parameter. 
   
   
     15. The method of  claim 14  wherein the pressure is controlled to be maintained at a selected value prior to actuation of each air gun.